Carol Thatcher made multiple references describing a French mixed-race tennis player as a "golliwog", "half-golliwog" and "golliwog Frog", sources say.

Thatcher, dropped from BBC1's The One Show after the programme said she refused to adequately apologise for her comments in the programme green room, made multiple remarks in front of 12 people, including presenter Adrian Chiles, comedian Jo Brand and a representative from the Comic Relief charity.

Today, The One Show insiders confirmed a story in the Times that reported that Thatcher had made variations on her comment several times in the green room.

"'Golliwog' wasn't the half of it, it is much worse than what has come out," a programme source told MediaGuardian.co.uk.

Thatcher, the daughter of former prime minister Lady Thatcher, was dropped as a roving reporter from The One Show on Tuesday night after refusing to make a full apology about her remark. Her spokeswoman said it had been an off-the-cuff remark "made in jest".

Today, Thatcher's representative said all the reports on what had happened in the green room, including today's, were "uncorroborated".

The BBC said complaints over its handling of the situation had now reached 3,348, while the number of calls and emails supporting the corporation had doubled from 60 yesterday to 133 today.

Sources have said Thatcher is considering selling her side of the story to the Mail on Sunday this weekend.

It is thought the story could rumble on into the weekend, with other sources saying that Thatcher is considering writing a tell-all piece for the Mail on Sunday. However, she is said to be worried that any further attack on the BBC could damage her chances of ever working there again, with one source saying she wanted to see an end to the row.

Thatcher currently has several projects on the go with the BBC – she is due to film a programme for the Inside Out regional current affairs strand about her mother and is also reported to be taking part in BBC1's geneaology series Who Do You Think You Are?

She is understood to have flown out to Italy this morning as part of a European speaking tour. She was seen at London's City airport, and when asked about the row described it as "total bollocks".

A source said the atmosphere among the team on The One Show was currently one of disbelief that the story had become so big.

Chiles is also said to be annoyed at the way he has been portrayed in media coverage amid suggestions he and Brand leaked the story.

MediaGuardian.co.uk understands the story originated from a member of the production team who mentioned it to a friend, who in turn told a reporter on the Times, which broke the story.

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